Musical entertainers

You know, music entertainers (boy bands, girl bands, major label singers)  are also musicians too-- they practice for hours for the support of their fans. What's the difference between them and orchestral performers? In orchestra concerts, there is courtesy and the audience applauds either between movements, or after the concert itself. But if you're like Super Junior, or Justin Bieber, you have people screaming when you sing, judge you when you dance and rank on your looks. Honestly, if you wanted to be judged by your looks, you might as well have tried to become a model. If you wanted to be judged by your dancing skills, then you should have be a dancer, so please. Take this into consideration, even though there is much love for these type of artists, they're still artists and there has to be some sort of courtesy out there.